Cationic polymers are well known in the art. For example in liquid cleansers, cationic hydrophilic polymers such as Polymer JR.RTM. from Americhol or Jaguar.RTM. from Rhone Poulenc have been used to enhance delivery of benefit agents (EP 93,602; WO 94/03152; and WO 94/03151).
Cationic polymers have also been used in bar formulations. U.S. Pat. No. 3,761,418 to Parran, Jr., for example, teaches detergent composition (including bar soaps) containing water insoluble particulate substances such as antimicrobial agents and certain cationic polymers to enhance deposition and retention of such particulate substances. Although bar soap formulations are used in the examples, all of the formulations are primarily structured with soap and/or fatty acid. Further, not only are benefit agents (oils/emollients) not disclosed, but it would be expected that hydrophobic structurants would interfere with deposition of any such oils/emollients.
WO No. 95/26710 to Kacher et al. (assigned to P&G) teaches skin moisturizing and cleansing bar containing skin cleansing agent and lipid moisturizing agent. A preferred optional ingredient is one or more cationic polymeric skin conditioning agent added to provide a tactile cue. Again, however, the bar is made of a rigid crystalline network structure consisting essentially of selected fatty acid soap material. Applicants have found such fatty acid soap material to be detrimental to deposition.
U.S. Pat. No. 5,425,892 to Taneri et al. teach personal cleansing freezer bars comprising a skeleton structure of neutralized carboxylic acid soap. The patent teaches polymeric skin feel aids, water soluble organics and oils. However the bars, as noted, have a distinctive carboxylic acid structure differing from bars of the invention containing relatively large amounts of hydrophilic structurant.
Hydrophilic structured bars themselves are also taught, for example, in U.S. Pat. No. 5,520,840 to Massaro et al. or U.S. Pat. No. 5,540,854 to Fair et al. There is no teaching in these references, however, of cationic polymers and no suggestion that such cationics could enhance deposition of oil/emollients in bars containing relatively large amounts of hydrophilic structurant. Further there is no teaching or suggestion in this or any other reference of a critical cationic to surfactant ratio above which deposition of oils/emollients is significantly enhanced or that cationics must have minimum level of charge density.
Finally, U.S. Pat. No. 5,262,079 to Kacher et al. teaches firm, mild neutral pH cleansing bars comprising 5-50% by wt. monocarboxylic fatty acids (which provides skeletal structure), 20 to 65% bar firmness aid and 15% to 55% water. The bars may contain optional polyols (0-40%) as "bar firmness aids". The bars are primarily fatty acid structured and the only bar firmness aids exemplified are isethionate (i.e., they do not have minimum levels of hydrophilic to hydrophobic structurant). Further, cationics disclosed are guar, quaternized guar etc., all of which have charge density below 0.007. There is thus no recognition that only cationic polymers having minimum charge activity are adequate for purpose of the invention.